The present disclosure relates to an imaging lens that is suitable for a compact imaging apparatus using an imaging device such as a CCD (Charge Coupled Device) and a CMOS (Complementary Metal Oxide Semiconductor), and has a large aperture, for example, with an F number of about 2.0. Examples of the compact imaging apparatus may include a digital still camera and a mobile phone with a camera. The present disclosure also relates to an imaging apparatus that uses such an imaging lens.
Imaging apparatuses have been known such as a mobile phone with a camera and a digital still camera that use a solid-state imaging device such as a CCD and a CMOS. In such imaging apparatuses, further reduction in size has been desired. Also in a lens for shooting to be mounted on such imaging apparatuses, reduction in size and reduction in total length have been desired.
Further, in recent years, also in compact imaging apparatus such as a mobile phone with a camera, a size thereof has been reduced and the number of pixels in the imaging device has been increased. For example, a model that includes an imaging device with a large number of pixels that may be thirteen million or more has been in widespread use. Therefore, high lens performance suitable for such a solid-state imaging apparatus with a large number of pixels has been desired also in the imaging lens to be mounted on such a solid-state imaging apparatus.
On the other hand, a brighter lens having a larger aperture has been desired in order to prevent increase of noise and degradation in sensitivity of the imaging device accompanying reduction in cell pitch in such an imaging apparatus. As such a compact and high-performance imaging lens, an imaging lens having a five-lens configuration is mainstream currently. As such an imaging lens having a five-lens configuration, for example, Japanese Unexamined Patent Application Publication No. 2011-257448 (JP2011-257448A) and Japanese Unexamined Patent Application Publication No. 2012-008490 (JP2012-008490A) have been known.